The present invention relates to a control lever for heavy machinery and, more particularly, to a control lever including a fixed grip portion to help support an operator while driving or maneuvering the machinery, while reducing the potential for inadvertent motion of the control during operation.
Many types of equipment place an operator in a position where the operator moves with an arm or other device attached to the machine. The operator may be standing or sitting while maneuvering the equipment. As such, from this position, the operator must attempt to counteract the inertia forces associated with motion and operation of the machinery.
Because of these forces, it is desirable for manufacturers to provide a fixed grip for the operator that also contains the controls necessary to move or position parts of the equipment. Such a design would help address issues associated with operator comfort, safety and support while operating the equipment.
Current joy stick and control designs do not address the sudden inertia shifts which may or may not occur as a result of the operator's decision to activate or cease activation of a moving function of the machine to which the operator is part of the movement. In addition, current designs force the operator to grasp a control lever that pivots at or near the base of the hand. These designs do not offer adequate fixed support for the operator and may cause sudden inadvertent movement of the equipment.
With the split grip control lever according to the present invention, inadvertent motion caused by inertia shifts in the operator's environment can be substantially eliminated. The grip includes a movable control portion that is operated by the thumb and index finger and a fixed portion that serves to support the operator's hand. This construction enables the operator to let go of the top movable portion of the control lever while maintaining a firm grasp of the fixed base portion of the grip.
In an exemplary embodiment of the invention, a split grip control lever includes a fixed base portion and a movable upper portion that is separately pivotable relative to the fixed base portion. The movable upper portion and the fixed base portion define a substantially continuous profile. The movable upper portion and the fixed based portion define structure for an operator to resist effects of all external forces via one hand while maintaining control of the movable upper portion with the same hand.
A control device is positioned within the fixed base portion, and the movable upper portion includes a control shaft coupled with the control device. Preferably, the control device is disposed at a substantially central position relative to the lever profile such that a pivot point of the control shaft is centrally disposed relative to the lever profile. In other words, the control device is disposed at a position spaced from a surface to which the fixed base portion is fixedly secured at a substantially central position relative to the lever profile. The control device may be an electromechanical control device or an optical control device.
The substantially continuous profile is preferably shaped to fit a user's hand. In this context, the profile may be configured for a user's right hand or a user's left hand. As noted above, the movable upper portion is disposed relative to the fixed base portion and sized for manipulation by a user's thumb and index finger, while the fixed base portion is disposed relative to the movable upper portion and sized to support the user's hand.
In another exemplary embodiment of the invention, a control lever for machinery includes a fixed base portion fixedly securable to a surface of the machinery such that the fixed base portion is immovable, and a control portion disposed adjacent the fixed base portion and movable relative to the fixed base portion. The control portion is separated from the fixed base portion via a split line and is contiguous with the fixed base portion to define a substantially continuous profile.
In yet another exemplary embodiment of the invention, a machine including a machine frame supporting at least one movable element is provided with the control lever of the present invention.